Apparatus and method for collecting meter data

ABSTRACT

A meter data collection device (20) including an antenna (52), a meter interface (60) receiving data from a meter (64), and a radio frequency (RF) stage (50). The RF stage (50) is coupled to the antenna (52) and is responsive to the meter interface (60). The RF stage (50) is operable for transmitting the meter data over a control channel of a wireless communication system.

This application is a continuation of application Ser. No. 08/540,385,filed Oct. 6, 1995, now abandoned.

FIELD OF THE INVENTION

This invention relates generally to meter data collection, and moreparticularly to collecting meter data using a wireless communicationsystem

BACKGROUND OF THE INVENTION

Currently, utility meter reading is generally a manual operation.Typically, every month or two months, a meter reader from one of theutility companies (gas, water, power) walks door to door to visuallyread the utility meter connected to each house and record the measureddata. Data collected is then entered into computers and fed back intocentral computers for billing and other processing. Due to the laborintensive nature of utility meter reading, it would be desirable toprovide a more efficient automated method of performing meter reading.

A conventional automated method is to connect a meter to a phone line.Then, a person at the utility company can call the meter to receive thedata. Using the public telephone system for performing meter reading hasseveral disadvantages. For example, to transmit data, a circuit-switchedconnection using modems is typically used. Circuit-switched connectionsare relatively inefficient for transmitting burst data, such as datafrom a meter. Also, a meter has to be connected to a phone line. Thephone line then has to be connected to a phone line termination withinthe house. Thus, a phone company representative typically provide theadditional phone line connection to the meter. The added phone lineconnection adds to installation costs and is inconvenient.

Another conventional method of collecting meter data is performed bystandard telemetry systems such as the system described in U.S. Pat. No.5,438,329. However, for mass market telemetry to be effective, it shouldbe ubiquitous and low cost. Conventional wireless telemetry systems,such as the system described U.S. Pat. No. 5,438,329, is a high costalternative due to the considerable dedicated infrastructure used fordata collection.

Accordingly, there is a need for a more efficient and convenient methodand apparatus for providing automated meter reading.

SUMMARY OF THE INVENTION

The present invention addresses this need by providing a meter datacollection device, a method of collecting meter data, a wirelesscommunication system, a communication unit within a wireless cellularcommunication system, and a meter data storage device. The meter datacollection device includes an antenna, a meter interface receiving datafrom a meter, and a radio frequency (RF) stage coupled to the antenna.The RF stage is responsive to the meter interface and is operable fortransmitting the meter data over a control channel of a wirelesscellular communication system.

The method of collecting meter data from a utility meter includes thesteps of receiving meter data from the utility meter, storing thereceived meter data in a memory device, and transmitting the storedmeter data over an air interface. The air interface includes a controlchannel of a wireless cellular communication system.

The communication unit in a wireless cellular communication systemincludes a base station interface module receiving meter data, a networkinterface module in communication with a telephone network, and a switchmatrix coupling the base station interface module and the networkinterface module.

The wireless communication system includes a meter data collectiondevice, a first communication unit in communication with the meter datacollection device, and a second communication unit coupled to the firstcommunication unit. The second communication unit comprises a firstcommunication unit interface module receiving meter data from the firstcommunication unit, a network interface module in communication with atelephone network, and a switch matrix coupling the first communicationunit interface module and the network interface module.

According to a further aspect of the invention, a meter data storagedevice in communication with a communication unit in a wirelesscommunication system and in communication with a processor is provided.The meter data storage device comprises an input device receiving meterdata from the communication unit, a computer readable memory storing themeter data, and an output device transmitting at least some of the meterdata to the processor.

The invention itself, together with its intended advantages will best beunderstood by reference to the following detailed description, taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a preferred embodiment of a wirelesscommunication system.

FIG. 2 is a block diagram of the meter data collection device of FIG. 1.

FIG. 3 is a more detailed block diagram of the wireless communicationsystem of FIG. 1.

FIG. 4 is a block diagram of an alternative embodiment of the meter datacollection device of FIG. 1.

FIGS. 5 and 6 are flow charts detailing a preferred method of collectingmeter data.

FIGS. 7-12 are diagrams illustrating data formats for messages that maybe transmitted over the control channel used by the wirelesscommunication system of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a preferred embodiment of a wireless communicationsystem 18 is illustrated. The wireless communication system 18 includesa processing center 34, a first communication unit 22, a secondcommunication unit 26, a public switch telephone network (PSTN) 30, anda metered data collection device 20. The first communication unit 22 isconnected to the second communication unit 26 via a standard cellularinfrastructure interface 24, such as a T1 line. The first communicationunit 22 is coupled to the meter data collection device 20 via an airinterface 23. More particularly, the air interface 23 includes a controlchannel of a wireless communication system. In the preferred embodiment,the air interface 23 is a Advanced Mobile Phone System (AMPS) ornarrowband AMPS system as defined in Telecommunications IndustryAssociation (TIA) Interim Standard (IS) IS-91 available from TIA at 2001Pennsylvania Avenue N.W., Washington, D.C. 20006.

The second communication unit 26 is connected to the processing center34 via a data communication link 32. The second communication unit 26 isconnected to the PSTN 30 via a telephone network communication link 28.Preferably, the telecommunication link 28 is a T1 line. In the preferredembodiment, the first communication unit 22 includes a base station andan antenna. The second communication unit 26 is a communication unitwithin a cellular system that includes a wireless access unit 38 and anadjunct processor 36, preferably a home location register (HLR). Theprocessing center 34 preferably processes utility meter collection datasuch as power, gas or water meter information. The processing center 34is typically located at an appropriate utility company computer center.

During operation, the meter data collection device 20 at a predeterminedinstant of time or in response to a command from the secondcommunication unit 26 collects meter data that has been read from autility meter connected to the house or other residence. The meter datareceived from the utility meter is temporarily stored in a memory withinthe meter data collection device 20. The stored meter data is thentransmitted over the air interface 23 to the first communication unit22. The meter data received at the first communication unit 22 is thentransmitted over the cellular interface 24 to the second communicationunit 26. The second communication unit 26 then routes the data either tothe PSTN 30 or to the processing center 34. At the processing center 34the meter data is stored within a memory storage device, and thenprocessed in order to place the meter data into a suitable format forbilling.

Referring to FIG. 2, a preferred embodiment of the meter data collectiondevice 20 is illustrated. The meter data collection device 20 includesan RF stage 50 connected to an antenna 52, a controller 54, and a meterinterface 60. The meter interface 60 is connected to a standard utilitymeter 64 via a suitable electrical connection 66. The meter interface 60may be a conventional interface such as described in U.S. Pat. No.4,350,980. The controller 54 is connected to the meter interface 60 andis also connected to the RF stage 50 via a second electrical connection68. The controller 54 includes a processor 56 and a memory 58 connectedto the processor 56. The RF stage 50, the antenna 52, and the controller54, are preferably circuit components taken from a standard cellulartelephone, such as a Motorola Microtac II.

During operation, data from the meter 64 is transmitted to the meterinterface 60, producing data in a digital format suitable for use by thecontroller 54. The controller 54 receives the digitally formatted meterdata and stores this digital data into the memory 58. The controller 54thereafter processes the data using processor 56 and transmits the meterdata to the RF stage 50 over the second electrical connection 68. The RFstage 50 then performs standard RF processing such as modulation andthen transmits the modulated meter data via antenna 52 over a controlchannel of the air interface 23. In a similar manner, a control signalreceived at antenna 52 is demodulated by RF stage 50 and sent tocontroller 54. The controller 54 then polls the meter interface 60 tocollect data from the meter 64.

Referring to FIG. 3, a preferred embodiment of the first communicationunit 22, the second communication unit 26 and the processing center 34is illustrated. The first communication unit 22 preferably includes abase station 73, such as a Motorola Supercell SC9600™ base station, witha transceiver 72. The base station 73 is connected to an antenna 70. Thesecond communication unit 26 includes the wireless access unit 38. Thewireless access unit 38 preferably includes a base station interfacemodule 74 which is connected to the base station 73, a switch matrix 76connected to the base station interface 74, and a network interfacemodule 78. The network interface module 78 is connected to the PSTN 30via the telecommunication link 28, and is connected to the switch matrix76.

The second communication unit 26 also includes an adjunct processor 36,which is preferably a HLR. The processor 36 includes a memory 88 and aprocessing center interface 90. The processing center interface 90 isconnected to the processing center 34 via the computer communicationlink 32.

The processing center 34 includes a memory storage device 80. The memorystorage device includes an input device 82, a computer readable memory84, and an output device 86.

The second communication unit 26 receives meter data from the basestation 73 which was received over the air interface 23 by the antenna70. Base station interface module 74 receives the meter data and passesthe meter data to the switch matrix 76. The switch matrix 76 routes themeter data to either the network interface module 78 for transmission tothe PSTN 30 or to the adjunct processor 36. Meter data within theadjunct processor 36 is stored in memory 88 and then transmitted to theprocessing center 34 using the processing center interface 90 and thecommunication link 32. Within the processing center 34, the memorystorage device 80 receives the meter data at the input device 82 andstores the meter data within the computer readable memory 84. The storedmeter data within the memory 84 may then be transmitted from theprocessing center 34 using the output device 86. Typical applicationswhich require reading the meter data from the computer readable memory86 include utility billing processing routines.

In this manner, meter data collected from the meter 64 and transmittedover the air interface 23 to the base station 73 is further transmittedby the second communication unit 26 and sent to the processing center 34within a utility company computer center. Such meter data may becollected in response to an operator command at the processing center34. Alternatively, the processing center 34 may be programmed toautomatically collect data from each meter collection device 20 incommunication with the base station 73.

A particular preferred embodiment of a method of collecting meter datafrom the meter data collection device 20 will now be described withreference to FIGS. 5 and 6. Three classes of operation may be supportedat the meter data collection device 20. These are polling, operationalsupport, and remote control.

Polling is the process of collecting data associated with the meter andreporting it to the communication unit 22. Several modes of operationfor polling are supported. A typical polling technique is a bulk poll,where data is accumulated over several days and is collected via a pollrequest from the communication unit 22. Counters within the controller54 are subsequently reset. A second polling technique breaks a timeperiod, such as a day, into a plurality of time intervals. Usage ratesat each time interval are then collected and stored in the memory 58until such time the device 20 is polled. In response to a poll, each ofthe time intervals are reported and then reset. The second pollingtechnique may be useful if the utility company is billing on a time ofday usage basis. A single poll sequence at an off peak hour would allowthe system 26 to gather rate information for the entire day.

The second mode of operation involves operational support features. Suchfeatures include initialization, alarm setting, and diagnostic testing.A typical operational support feature is supported by the firstcommunication unit 22 sending a command to the device 20 instructing thedevice 20 to set a desired polling technique. Another example ofoperational support is when the communication unit 22 sends a command tothe device 20 to instruct the device 20 to reset counters or to performa diagnositc test such as a power up self test.

The third mode of operation deals with remote control. Devices 63connected to the processor 56 via a control interface 61 may becontrolled remotely from the utility processing center 34. For example,if it were desired to power down certain regions of a building duringperiods of the day, it could be done via this mode of operation.

A flow chart of the meter data collection device process, and inparticular that of the controller 54, is depicted in FIGS. 5 and 6. Thetypical state of operation will be that of monitoring the cellularsignaling channels as specified in the air interface standard, which isdenoted as step 100. In this step, the messages broadcast over thesignaling channels are continually decoded in an effort to determine ifthe system desires to address this unit. Units may be globally as wellas individually addressed.

If a valid message is received for this unit, denoted as step 102, thecontroller 54 determines what action is requested. The first decisiontree, step 104, is to check for a poll request message, such as is shownin FIG. 7. If this check is positive, the controller 54 reads data fromthe meter 34 via the meter interface 60, step 108. The data is thenformatted for the response desired, step 110. An appropriate format isshown in FIG. 8. At this point the meter data collection device 20accesses a control channel as specified in the air interface 23, and thedata is sent to the communication unit 22, step 112. Thereafter,controller 54 returns to the monitor control channel mode at step 100.

If at step 104, the message is not a poll message, processing controlflows to step 106, where a check is made to determine if the message isan operations message. An example of an operations message is shown inFIG. 9. If the test at step 104 is positive, the controller 54ascertains what action is to be taken in response to the operationalmessage at step 122. The controller 54 then sends an acknowledgment tothe communication unit 22, step 124, and returns to monitoring thecontrol channels, at step 100. The format of an operations responsemessage is shown in FIG. 10. Typical actions performed by the device 22include resetting counters associated with the meter data, initializinginterval times maintained at the meter data collection device 20, andperforming diagnostics.

If at step 106, the message is not an operational message, processingcontrol flows to step 126, where a check is made to determine if themessage is a control message, such as the control message shown in FIG.11. If the test at step 126 is positive, the controller 54 selects acontrol element and performs an action using the selected controlelement, step 128. Subsequent to successful execution of the action, thesystem is accessed and an acknowledgment message is sent to thecommunication unit 22, step 130. The format of the acknowledgmentmessage is shown in FIG. 12. Processing control then returns tomonitoring the control channel at step 100.

If at step 126, the message is not a control message, processing controlflows to step 132, where the message is rejected and the communicationunit 22 is informed of the rejected message. Control then returns tostep 100.

A second flow of execution that can occur from step 100 deals with thetime control aspect of the system 18. Since time based operation of thesystem 18 is supported, the controller 54 may maintain time intervalsand store data accordingly. Step 114 denotes expiration of a one minutetimer 65 within the meter data collection device 20. When the timer 65expires, current time of the system 18 is incremented and stored, step116. That time is then compared to threshold intervals set through anoperations message sequence, at decision step 118. If an interval hasnot been exceeded, control returns to step 100. If an interval isexceeded, the meter is read and the data from the meter is stored incontroller memory 58 for that particular interval, at step 120. Controlthen returns to the monitor control channels, at step 100.

FIGS. 7 through 12 represent the downlink and uplink message formats,respectively, for the meter polling sequence. Note that other messagesexist for different operations. The messages follow the extendedprotocol specification of the TIA IS-91 standard. Several new messagetype have been added, called telemetry poll message, and are defined as1001 0000, operations messages, defined as 1001 0010, and controlmessages, defined as 1001 0001. All fields are defined in the airspecification. Those skilled in the art will appreciate that additionalmessage types may be defined as needed for other operations.

The preferred embodiments described above provide an automated meterdata collection device. This preferred embodiment has many benefits. Forexample, cellular represents widespread infrastructure already deployedand cost amortized for a different purpose, that being voice basedservices. Leveraging of that infrastructure for telemetry servicesprovides a low cost system to effect widespread coverage. Additionallyno manual meter readers are required.

Further advantages and modifications of the above described apparatusand method will readily occur to those skilled in the art. Theinvention, in its broader aspects, is therefore not limited to thespecific details, representative apparatus, and illustrative examplesshown and described above. Various modifications and variations can bemade to the above specification without departing from the scope orspirit of the present invention, and it is intended that the presentinvention cover all such modifications and variations provided they comewithin the scope of the following claims and their equivalents.

What is claimed is:
 1. A utility meter data collection device having aplurality of operational modes, comprising:an antenna; a utility meterinterface receiving utility usage data from a utility meter; a radiofrequency (RF) stage coupled to the antenna and responsive to theutility meter interface; and a controller in communication with theutility meter interface, the radio frequency stage and a control device,in a first mode, the controller instructing the RF stage to transmit theutility usage data over a control channel of a wireless cellularcommunication system and in a second mode the controller instructing thecontrol device to perform a predetermined action.
 2. The device of claim1, wherein the controller includes a processor and a memory, the memorystoring the utility usage data.
 3. The device of claim 1, wherein theutility meter interface comprises an analog to digital converter.
 4. Thedevice of claim 1, wherein said utility meter is selected from the groupconsisting of an electricity meter, a water meter, and a gas meter.
 5. Acommunication unit in a wireless cellular communication system, thecommunication unit comprising:a base station interface module receivingutility usage data from a utility usage-data collection device; anetwork interface module in communication with a telephone network; aswitch matrix coupling the base station interface module and the networkinterface module; and a processor responsive to the switch matrix and incommunication with a utility processing center, the utility processingcenter remotely instructing the utility usage-data collection device totransmit the utility usage data over a control channel of the wirelesscommunication system, and the switch matrix routing the utility usagedata to one of the network interface module and the processor.
 6. Thecommunication unit of claim 5, further comprising a memory storagedevice responsive to the processor and storing the utility usage data.7. The communication unit of claim 6, wherein the utility usage data istransmitted from the memory storage device to the utility processingcenter.
 8. A wireless communication system comprising:a firstcommunication unit; a utility usage-data collection device having aplurality of modes of operation, the utility usage-data collectiondevice responsive to the first communication unit and operable fortransmitting utility usage data to the first communication unit over acontrol channel of the wireless communication system; and a secondcommunication unit coupled to the first communication unit, the secondcommunication unit comprising:a first communication unit interfacemodule receiving the utility usage data from the first communicationunit; a network interface module in communication with a telephonenetwork; and a switch matrix coupling the first communication unitinterface module and the network interface module.
 9. The system ofclaim 8, wherein said first communication unit comprises a base station.10. The system of claim 8, wherein said wireless communication systemcomprises a radiotelephone system.
 11. The system of claim 8, whereinsaid wireless communication system is selected from the group consistingessentially of a frequency division multiple access system, a timedivision multiple access system, and a code division multiple accesssystem.
 12. The device of claim 1, wherein in the first mode, thecontroller is responsive to a message from a utility processing center.13. The device of claim 12, wherein the utility processing centercomprises a billing center.
 14. The device of claim 1, wherein thepredetermined action comprises adjusting electricity usage in at least aportion of a building.
 15. A method for controlling a utility usage-datacollection device, the utility usage-data collection device coupled to autility meter and responsive to a wireless communication system, thewireless communication system in communication with a utility processingcenter, the method comprising the steps of:receiving, by the utilityusage-data collection device, a message over a control channel of thewireless communication system; and based on the message, entering one ofa plurality of modes of operation.
 16. The method of claim 15, whereinthe message is selected from the group consisting essentially of: atelemetry poll message, an operations message and a control message. 17.The method of claim 16, wherein the one of the plurality of modes ofoperation is selected from the group consisting essentially of: apolling mode, an operational support mode and a remote control mode. 18.The method of claim 15, further comprising the step of:prior toreceiving the message by the utility usage-data collection device,receiving, by the wireless communication system, a command from theutility processing center.
 19. The method of claim 18, wherein themessage is received by the utility usage-data collection device inresponse to the command.